Add flannel-external-ip when there is a k3s node-external-ip

[manuelbuil]

Signed-off-by: Manuel Buil [email protected]

Proposed Changes

Make sure that if node-external-ip is defined in the k3s config, the annotation flannel.alpha.coreos.com/public-ip-overwrite is added for each node, so that flannel can configured itself correctly

Types of Changes

Bugfix

Verification

1 - Create two VMs which do not belong to the same subnet (e.g. in different public clouds). These VMs must have a public IP
2 - Deploy k3s with the following config in one VM:

write-kubeconfig-mode: 644
token: "secret"
node-external-ip: $SERVER_PUBLIC_IP
flannel-backend: wireguard-native

3 - Deploy k3s agent with the following config in another VM:

token: "secret"
server: "https://$SERVER_PUBLIC_IP:6443"
node-external-ip: $AGENT_PUBLIC_IP

4 - Run kubectl get nodes -o yaml. You should see the annotation: flannel.alpha.coreos.com/public-ip: and flannel.alpha.coreos.com/public-ip-overwrite: in both nodes. Both annotations must point at the publicIP of the node (what we passed as node-external-ip)

5 - Deploy a pod in each node/VM and ping between them. It should work

Testing

Not covered

Linked Issues

#6177

User-Facing Change

Fix flannel for deployments of nodes which do not belong to the same network and connect using their public IP

Further Comments